Industry and governmental entities have developed requirements for operating sophisticated electronics within harsh environments with extreme temperature, shock and vibration. For performing under these conditions, systems typically involve robust and sometimes sealed chassis assemblies which are called upon to perform with conduction-cooled circuit card assemblies (CCAs) or modules. These modules themselves are environmentally protected by enclosure within shell-like structures incorporating conduction frames or a three-dimensional conduction plate which conduct an electronically evolved heat energy to oppositely disposed sides or edge regions. When positioned within a chassis, the module engages a backplane as well as the oppositely disposed card slots or channels of robust thermally conductive conduction rails. The sides or edge regions of the modules are retained in substantial compression against the card slots by an expandable retaining device such as a wedge lock. With such compressive contact at the rail channels or slots, conductive heat transfer is provided from the modules into the conduction rail assemblies. These assemblies, in turn, are coupled in heat transfer relationship with chassis mounted finned heat sinks. As these thermal conduction-based systems evolved, so also did industry standards or specifications by organizations such as VITA (VME Industrial Trade Association). See for instance, IEEE Standard for Mechanical Core Specifications for Conduction-Cooled Eurocards (IEEE Std 1101.2-1992) concerning 6 U by 160 mm modules.
While the earlier conduction-based systems functioned adequately in carrying out heat dissipation, as electronic systems including power supplies have become more complex and functionally elaborate, heat generation at the modules has been seen to substantially increase and the conventional thermal conduction systems have been unable to perform adequately. Some conduction-cooled circuit card assembly installations are provided at locations having access to liquid cooling facilities which can be employed to accommodate the higher heat loads now being encountered. However, such facilities may be vulnerable to harsh environments, or may not be available or acceptable for a variety of reasons. For instance, if liquid cooling facilities are not already available on a given platform, designers will not wish to add them. Industrial entities engaged in developing the air flow-based conduction-cooled circuit card assemblies have resorted to such regressive design approaches as depopulating card carrying components, lowering clock speeds and the like to ameliorate the problem.
The inadequacies of the conventional approaches also have imposed limitations on the capability of retrofitting 20 or 25 year old platforms, for example, located in aircraft, with modern electronic systems.